This invention relates to apparatus for use in performing endoscopic surgical procedures. More particularly, the invention relates to an improved sheath for an endoscope for performing surgical procedures requiring fibrous tissue division, such as an endoscopic procedure for carpal tunnel release.
Because of the trauma associated with open surgical procedures, efforts have been made to develop endoscopic alternatives to all types of open surgical procedures. This invention relates to endoscopic alternatives to open procedure for surgical treatments requiring division of soft tissue, such as a tendon sheath or ligament. One example of such a procedure is the treatment of carpal tunnel syndrome, caused by the compression of the median nerve by the transverse carpal ligament. This treatment generally involves a procedure during which the carpal ligament is severed. While endoscopic versions of this procedure have been used in the past with varying degrees of success, continued development of endoscopic procedures to improve efficiencies and reduce patient trauma is always desirable.
For example, the prior endoscopic treatments of carpel tunnel syndrome described by Chow in U.S. Pat. No. 5,029,573 and by Brown in U.S. Pat. No. 5,323,765 use a slotted cannula design that is positioned under the transverse carpal ligament during the procedure. This places pressure on the nerve during the procedures and also places the nerve and tendons at risk of injury. Moreover, a number of prior endoscopic procedures for carpel tunnel release require two incisions (with one being in the palm) and/or require the introduction of one or more obturators into the carpel tunnel before insertion of the endoscope, which can cause additional trauma to the surgery site.
Accordingly, it is an object of the present invention to produce an endoscopic surgical apparatus suitable for use in various surgical procedures that involve the dissection and/or other retraction of fibrous tissue, including an endoscopic procedure for carpal ligament release as well as other endoscopic surgical procedures.
It is another object of the invention to provide an apparatus for performing such endoscopic surgical procedures with less trauma than existing endoscopic procedures.
It is another object of the present invention to provide an apparatus that facilitates the alignment of a cannula over the carpal ligament.
Although one preferred embodiment of this invention relates to carpal ligament release, it will be understood by those skilled in the art that the apparatus disclosed herein may be easily adapted to other surgical procedures.
Additional objects and advantages of the invention will be set forth in the description that follows, and in part will be apparent from the description, or may be learned by practice of the invention. The objects and advantages of the invention may be realized and obtained by means of the instrumentalities and combinations pointed out in the appended claims.